CBX Valve Guide Seal R&R

[panteradave]

Is it possible to change out the valve guide seals with the cylinder head still mounted, and without a super special valve spring compressor gizmo that I don't have? I've done this in the past on OHV engines by using an air chuck to pressurize a cylinder to keep the valve seated during disassembly/assembly. For the CBX, I think I can see how to pop the valve springs/keepers off to expose the valve seal for R&R, but I don't see an obvious way to compress the valve spring for reassembly.

Any ideas or advice on this?

Thanks,

Dave

[Larry Zimmer]

Dave,
Not certain from your post if you are looking to do this with the engine in the frame or pulled. Either way, you can check this post link from one of our premier Club engine builders, Preston. viewtopic.php?f=25&t=7490&p=57773&hilit=preston#p57773 . A very neat bit of fixturing to do the job. At the moment, I can't envision any fixture that could be fabricated to do the job with the engine in the frame. Even getting the keepers 'popped' in the frame might be a challenge. Just not enough clearance. If you do work on it without removing the head, be certain to plug all oil drain holes in the head before removing anything. One of those keepers down a drain and *#&%@ !!

[panteradave]

It looks like this is more of a remove the head kind of job. I was sort of hoping that the valve seals could be replaced without breaking into the engine, but probably not.

Thanks for the feedback.

Dave

[EMS]

It looks like this is more of a remove the head kind of job. I was sort of hoping that the valve seals could be replaced without breaking into the engine, but probably not.

Thanks for the feedback.

Dave

Dave:

I have replaced valve guide seals on two of my CBXes last year. Taking the head off is not that bad. It also gives you the chance to address some other issues, like carbon build-up, cam chain replacement and valve re-seating.
I did not take the motors out of the frames.

[NobleHops]

Exhuming this topic for a moment, I am gearing up to pop the top on at least one engine this winter. What's the best spring compressor tool to get for this job?

[NobleHops]

Further:

The black bike's engine is getting kinda noisy in the top end, and so I was thinking I'd remove the head, do the valve guide seals, have a look around. Thinking I ought to be prepared to inspect the cam caps for excessive wear, decarbon the piston and heads, lap the valves in, replace the oldham couplers and inspect the pistons, rings and cylinder bores, you know, WHILE I'M THERE.

What about the cam chain? Tensioners? Do the cylinders have to come out to replace the tensioners? And can I use the old cam chain to thread a new one?

TIA for some good grounding on the best approach to this project.

N.

[CopperCollar]

I have this one Nils, It works great.

http://www.ebay.com/itm/Valve-Spring-Co ... 1091wt_867

Price is right.

Not sure what others are using , would like to see other options though.

Preston has a nice set up but he does a gazillion heads.

Mike

[SteveG]

I have this one Nils, It works great.

http://www.ebay.com/itm/Valve-Spring-Co ... 1091wt_867

Price is right.

Not sure what others are using , would like to see other options though.

Preston has a nice set up but he does a gazillion heads.

Mike

+1 on this tool. Works great.

Steve

[daves79x]

Nils:

Think that's the compressor I have too - works fine and will last for as long as we need it to. Seals are easy to install - holler when you get there. Since yours is a running bike, I'd expect you to find no more than a valve clean-up and lapping needed. Don't remember the miles on your bike, but you will likely see 'black pepper' pits on the exhaust seats. Hand lapping will remove most if not too bad but if you can't get most of it, you'll need to have a shop clean the seats up with regular tools for that. The intakes will be fine. Any hand-lapping suction tool you like works fine - just get one with different cups on each end as the valves are pretty small.

You will likely find little to no wear on your other top-end components, other than cam chains. I wouldn't replace the long chain unless you are willing to split the cases and install the endless one. Personally wouldn't change either one - just make sure your tensioners are good and work properly. If you are going to pull the cylinders, yes, you can service the long chain adjuster. You might have the cylinders lightly honed and install new rings, but that's all. I'll loan you my ring compressors when you get there.

Best thing you'll do to quiet the top end is the oversize cam couplers. That's about it.

Dave

[NobleHops]

Nils:

Think that's the compressor I have too - works fine and will last for as long as we need it to. Seals are easy to install - holler when you get there. Since yours is a running bike, I'd expect you to find no more than a valve clean-up and lapping needed. Don't remember the miles on your bike, but you will likely see 'black pepper' pits on the exhaust seats. Hand lapping will remove most if not too bad but if you can't get most of it, you'll need to have a shop clean the seats up with regular tools for that. The intakes will be fine. Any hand-lapping suction tool you like works fine - just get one with different cups on each end as the valves are pretty small.

You will likely find little to no wear on your other top-end components, other than cam chains. I wouldn't replace the long chain unless you are willing to split the cases and install the endless one. Personally wouldn't change either one - just make sure your tensioners are good and work properly. If you are going to pull the cylinders, yes, you can service the long chain adjuster. You might have the cylinders lightly honed and install new rings, but that's all. I'll loan you my ring compressors when you get there.

Best thing you'll do to quiet the top end is the oversize cam couplers. That's about it.

Dave

Thanks all around Dave, that was just what I needed for grounding.

[EMS]

Three essential pieces for valve and stem seal removal:

Valve compressor, seal remover and an old plastic 35mm film cartridge.
You cut the cartridge (do a better job than I did) and slip it into the bore to protect the sides from marring them up with the tools.